The treatment of invasive fungal disease (IFD) has become a regular component of the complex treatment of hematological malignancies and IFD has become a problem in ICU patients as well. In an effort to improve the communication between physicians and clinical researchers, and to improve the understanding of the different terms used inconsistently to describe the same medical situation or diagnosis, a panel of experts first published definitions of opportunistic invasive fungal diseases in 2002. They were later accepted both in Europe and the USA and updated in 2008. We review the new data and characteristics of the various treatment approaches (prophylactic - empiric - pre-emptive - and targeted therapy) in the context of the level of certainty of the diagnosis of IFD (proven - probable - possible IFD) and finally we present the definitions used for the response to therapy (complete - partial remission - failure).